The semiconductor industry has seen tremendous advances in technology in recent years which have permitted dramatic increases in circuit density and complexity, and equally dramatic decreases in power consumption and package sizes. Present semiconductor technology now permits single-chip microprocessors with many millions of transistors, operating at speeds of tens (or even hundreds) of MIPS (millions of instructions per second) to be packaged in relatively small, air-cooled semiconductor device packages. Such microprocessors are typically mounted on printed circuit boards with other components, which are coupled with the microprocessor. Adhesion of the various laminate components to the printed circuit board during its life is a major concern in quality control. Such printed circuit board packages must also necessarily contain a great number of electrical connections, which typically comprise solder joints. Solder joints are also used for reasons of mechanical integrity. Quality concerns exist concerning the printed circuit board's long term integrity regarding preconditioning, temperature cycles, and temperature/humidity stresses.
Present methods and apparatus used to test adhesion of laminate components and solder joint integrity in printed circuit board packages are expensive. Further, existing testing methods and apparatus are limited in effectiveness due to the relatively long length of time required to complete testing. Finally, concerns exist in the industry with regard to the reliability of existing testing methods.